The present invention relates to a rotating electrical machine control system and vehicle drive system.
The rotating electrical machine control system is employed for controlling an operation state of a motor (which is one example of the rotating electrical machine) provided to an electric automobile, and is also employed for a so-called hybrid vehicle that includes a driving source such as an engine other than the rotating electrical machine and drives with driving force obtained appropriately from the rotating electrical machine and the other driving source.
According to Japanese Patent Application Publication No. JP-A-2004-222362, a voltage conversion device employed for such electric automobiles or hybrid vehicles has been developed. An example of the electric automobile is shown in FIG. 1 of JP-A-2004-222362, and an example of the hybrid vehicle is shown in FIG. 5 and the like of JP-A-2004-222362.
In a technique disclosed in JP-A-2004-222362, a control device 30 detects whether a boost converter 12 has failed based on a DC voltage Vb from a voltage sensor 10, an output voltage Vm from a voltage sensor 13, and a duty cycle in a switching control of NPN transistors Q1 and Q2. When a failure of the boost converter 12 is detected, the control device 30 controls an inverter 14 and an AC motor M1 to inhibit regenerative electricity generation of the AC motor M1 (see paragraphs [0076] and [0088]). As a result, the voltage conversion device capable of a failure process of the boost converter can be obtained without improving a withstand voltage-performance of a smoothing capacitor inserted on an input side of the inverter. Regarding a judgment on regeneration, according to the description of paragraph [0129], it can be understood that energy in the AC motor M1 is calculated based on an accelerator position and a motor rotational speed, and whether the AC motor M1 is in a power running mode or in a regeneration mode is determined based on the calculated energy. As should be appreciated, the reference numerals and the cited paragraphs are from JP-A-2004-222362.